Detection of large induction motor cage failure by novel analysis of the waveform of the start up current

Abstract

In the case of large induction motors, it is very important to quickly and safely identify the onset of failure. In that way one should take appropriate corrective measures to prevent significant damage. In this paper, the comparative diagnostics between two high-voltage large induction motors using the specific proposed waveform analysis of current during the direct-on-line start is presented. Using the previously recorded signals, a rotating current vector amplitudes for both machines are determined. Their shapes are analysed and the presence of the initial 100Hz stator current component, indicating the existence of a rotor failure, is observed.

Keywords

• large induction motor
• machine diagnostics
• rotating current vector
• 100Hz component